1. Technical Field
The invention relates to a semiconductor structure and a method for manufacturing the same are disclosed and more specifically to a memory device and a method for manufacturing the same.
2. Description of the Related Art
Semiconductor structures include memory devices, used in storage elements for many products such as MP3 players, digital cameras, computer files, etc. As the application increases, the demand for the memory device focuses on small size and large memory capacity. For satisfying the requirement, a memory having a high element density is need.
Designers have developed a method for improving a memory device density, using 3D stack memory device so as to increase a memory capacity and a cost per cell. However, it is easy to degrade a memory window due to a poor electric field distribution during erasing and programming a memory.